Tiny off-grid solar inverter

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WAslayer

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My home office draws less than 400watt (thats when my gaming pc is running games) less than 300watt when gaming pc is off..

I was hoping I could get a single 500+watt solar panel, tiny off-grid inverter and use this to power the office during the day..? Have been trying to find a tiny inverter for this, but not having any luck..

Anyone have any leads/ideas..?
 
If you want to use a really tiny inverter ie 500w you normally don't get ones with a charge controller

So would have to buy one sepperate

With that cost it makes sense to just buy one with a built in mppt ie 1kw normally

The 500w will only produce 500w at noon morning and afternoon you get less non optimal sun angle if you have it on a stand/not roof you can sun track by angke change

Can add extra panel later if you see you cone up short
 
Not really concerned about charge controller, because I am not wanting to add batteries at all..
 
Ok i get it

I know that some growatts can be used like this, assume many others can too

But then one 500w will not cut it you can add more if it doesn't meet the need

Would need bigger array for lower light/angle losses doesn't see the panel output dip below load
 
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Off grid without batteries doesn't really make much sense.

If you have no grid power and only a single solar panel and a cloud goes over the sun then there goes all your power.
 
Yea you have to overspec the array , so if this is the aim i would still get a battery as a buffer even If battery backup/cycling isn't part of the plan
 
ie some guys say get like 2kw from a 8kw array ie 25% in bad weather

So to meet that 300w load you would need over 1200w array and then might still from time to time get that perfect storm that load exceeds output and trips
 
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I already have a ecoflow river pro powering the office during loadshedding..

I am happy to add an additional panel if I see it's required..
 
My hurdle at the moment is finding a suitable inverter, hence the reason for this thread..
 
Yea adding a battery would be cheaper than sizing the array for no battery (salt shooting from the cuff)

And make finding an inverter a lot easier
 
I have the ecoflow as a backup if the array falls short of consumption due to weather and it happens to be loadshedding at the same time..

Adding a battery, since I wouldn't want to bother with LA types, would just add unnecessary costs and I imagine the inverter would then also be more expensive, given the added charge controller etc..
 
WAslayer said:
I have the ecoflow as a backup if the array falls short of consumption due to weather and it happens to be loadshedding at the same time..

Adding a battery, since I wouldn't want to bother with LA types, would just add unnecessary costs and I imagine the inverter would then also be more expensive, given the added charge controller etc..
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You will find inverter with ac charger and no mppt

Very unlikely to find an inverter with an mppt but no charger

ie the growatt comes with inverter/charger/mppt as one package

So you can try it and see how it works if it gives you head aches you can later add a battery

And the same with panels
Getting a unit that can handle a bigger size array can see you expand if you need more panels otherwise you will be forced into batteries
 
What Ecoflow do you have? Why not just charge that up with the appropriate panel?

I still think PV without batteries is going to be a huge pain, you can go from full power to almost no power in an instant when there are clouds. That's just not a reliable power source.
 
DrJohnZoidberg said:
What Ecoflow do you have? Why not just charge that up with the appropriate panel?

I still think PV without batteries is going to be a huge pain, you can go from full power to almost no power in an instant when there are clouds. That's just not a reliable power source.
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Yea you would need an oversized array to have enough output in the morning and afternoon

And for bad light
 
How much is a lithium battery going to cost me, that will cover a 4.5 hour loadshedding slot at a 300watt per hour power draw..?
 
WAslayer said:
How much is a lithium battery going to cost me, that will cover a 4.5 hour loadshedding slot at a 300watt per hour power draw..?
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A single 100ah battery would just fall short

ie you would most likely need 1.5kwh working on 90% efficiency
(300w x 4.5 /0.9 =1500wh/1.5kwh)


Have seen listings for R6.6k for 100ah 1280w/1.28kwh (100x 12.8v)

But if you had one panel and a 100ah you should be fine as the panel will compensate
ie if the panel produced only a 100w bad weather it reduces the load to 200w

Meaning you would need a 1kwh battery so one 100ah 1.28kwh will suffice

If it produces more naturally you can weather longer outages
 
And I can't just add a ATS in the mix, feeding grid and PV into it and out into the ecoflow..?

I have the ecoflow, for all intents and purposes, it's a battery..?
 
WAslayer said:
And I can't just add a ATS in the mix, feeding grid and PV into it and out into the ecoflow..?

I have the ecoflow, for all intents and purposes, it's a battery..?
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Yea the inverter gets connected to grid battery and panels
Edit it will use eskom and switch over to batteries if you set it that way
Or be in solar mode ie focus more on power saving but the battery may not be full all the time as the battery wil supplement when shading occurs or low light conditions



And can then connect ecoflow to it to charge as a backup

The ecoflow has panel capabilities?
why not just connect a panel to it

And use it as you backup device ,or is it missing functionality that you want to get another device for ie ups
 
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